Steam and air injector for furnaces



(No Model.

F. E. FAHRIG.

Q STEAM AND AIR INJECTOR FOR FURNACES. No. 314,925.

Patented Mar. 31, 1885.

71in Aito nay.

UNITED STATES PATENT OFFICE.

FRANK E. FAHRIG, OF SGRANTON, PENNSYLVANIA.

STEAM AND AIR INJECTOR FOR FURNACES.

SPECIPICATIOII forming part of Letters Patent No. 314,925, dated March31, 1885.

Application filed June 1, 1883.

(No model.)

Scranton, in the county of Lackawanna and State of Pennsylvania, haveinvented certain new and useful Improvements in Steam and Air Injectorsfor Furnaces; and I do hereby declare the following to be a full, clear,and exact description of the same, referen ce being had to theaccompanying drawings, forming a part of this specification, and to thefigures and letters of reference marked thereon.

In culm-burning furnaces as ordinarily constructed a blast of steam andair is injected into the ash-pit and up through the grate-bars thereof,so as to facilitate the combustion of the culm supported on thegrate-bars, and the means employed for producing said blast consists ofa blower pipe or nozzle of substantially the shape of two frustums ofcones placed with their smaller ends together and connected to a pipeleading into the ash-pit, and of a single steam jet pipe inserted ashort distance within the flaring mouth of the said blower-nozzle andadapted to discharge ajet of steam of from three-sixteenths toeight-sixteenths of an inch in diameter centrally into and through saidnozzle, so as to create apartial vacuum therein and cause a quantity ofair to be drawn in and forced with the steam into the furnace. This formof injector is, however, very objectionable, because of the exceedinglyloud noise it produces while in operation. It has been my primaryobject, therefore, to provide an injector equally as effective as thoseat present in use, if not more so. and one whose operation shall bepractically, noiseless; and to this end my invention consists incombining with the old or any other suitable form of blower pipe ornozzle a steamsupplying device,by which the steam is delivered into saidblow pipe or nozzle in a number of fine jets arranged preferably in acircular, oval, or square series and adapted to converge to a pointwithin the nozzle.

In practice I prefer to effect the delivery of a circular series ofconverging jets by means of the circular perforated pipe arrangedcentrally within the mouth of the nozzle, so that the air drawn in maypass around as well as through the said circular pipe; and I alsopreferably support said circular pipe or perforated tubular ring so thatit may be adjusted back and forth within the nozzle till the point isreached where the maximumeffect is obtained.

In the accompanying drawings, Figure 1 represents a sectional view of aculm-burning furnace, showing my improved injector applied thereto. Fig.2 is a perspective view of the circular steam jet pipe detached.

Similar letters of reference in the several figures denote the sameparts.

A represents the ash-pit of the furnace; B, the grate of the same; 0,the pipe or duct for carrying the blast of steam and air into theash-pit; D, the blower pipe or nozzle into which the air is drawn by thesteam-jets, and E the circular perforated pipe arranged within the mouthof the nozzle D and connected to asteam-supplypipc, F, leading from thesource of steam-supply. The pipe F is supported by abracket, G, orotherwise conveniently, and is adapted to be moved in and out throughthe said bracket, so as to adjust thecircular pipe the desired distancewithin the nozzle. The perforations e in the circular pipe E arearranged so that the jets of steam issuing from them will converge orfocus at a point down within the nozzle, as shown by the dotted lines,Fig. 1, and cause the air to be drawn into the nozzle through as well asaround the circle of live steam, as shown by the arrows, Fig. 1, and tobe forced with the steam into the furnace with little or no noise ascompared with the devices at present in use.

As a means of effecting the adjustment of 85 the steam-delivering ring,I have shown the pipe F screw-threaded at its upper end, so as to adaptit to be screwed up or down the pipe or support to which it is designedto be connected.

I am aware of the patent granted to Han cock, March 1, 1864, No. 41,770,and do not claim a central cross-tube with central induction branchpipe, such tube connecting a series of hollow perforated rings, as oneof the objects of my invention is to avoid obstructing the centralair-passage as much as possible, and also to have the airpassage outsidemy perforated ring unobstructed to as great a degree as practicable.

I am also aware of the patent granted to Jones, May 29, 1877, No.191,438, and do not claim an inductionpipe applied centrally acrossstraight perforated tubes.

Having thus described myinvention, I claim as new 1. In a steam and airinjector for furnaces, the combination, with a nozzle, of a circularsteam delivery pipe arranged therein and having perforations arranged soas to focus or converge thejets issuing therefrom'and draw a supply ofair into the nozzle through and around the circular delivery pipe,substantially as described.

2. A hollow steam-injecting annulus provided with jet-perforations and asupportingextension outside its central air-passage, in combination withan air-cone, whereby an un obstructed central passage for the air drawnthrough the cone by the steam-jets is secured

